\(=\left(-16-\dfrac{2}{7}\right)\cdot\dfrac{5}{3}+\left(28+\dfrac{2}{7}\right)\cdot\dfrac{5}{3}\)
\(=\dfrac{5}{3}\left(-16-\dfrac{2}{7}+28+\dfrac{2}{7}\right)\)
\(=12\cdot\dfrac{5}{3}=20\)
\(=\left(-16-\dfrac{2}{7}\right)\cdot\dfrac{5}{3}+\left(28+\dfrac{2}{7}\right)\cdot\dfrac{5}{3}\)
\(=\dfrac{5}{3}\left(-16-\dfrac{2}{7}+28+\dfrac{2}{7}\right)\)
\(=12\cdot\dfrac{5}{3}=20\)
tính: A = \(\dfrac{15}{34}+\dfrac{27}{21}+\dfrac{9}{34}-1\dfrac{15}{17}+\dfrac{2}{3}\)
B = \(16\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)-28\dfrac{2}{7}:\left(-\dfrac{3}{5}\right)\)
1. thực hiện phép tính
a. \(\dfrac{1}{3}-\dfrac{1}{2}\)
b. \(16\dfrac{2}{7}:\dfrac{-3}{5}-28\dfrac{2}{7}:\dfrac{-3}{5}\)
c. \(-3^3-\left(\dfrac{-1}{3}\right):\dfrac{4}{15}\)
d. \(9.\left(\dfrac{-1}{3}\right)^3+\dfrac{1}{3}\)
\(\dfrac{3}{\left(x-4\right).\left(x-7\right)}+\dfrac{6}{\left(x-7\right).\left(x-13\right)}+\dfrac{15}{\left(x-13\right).\left(x-28\right)}-\dfrac{1}{x-28}=\dfrac{-5}{2}\)
Tính hợp lí nếu có thể
a) \(\left(\dfrac{5}{7}-\dfrac{7}{5}\right)-\left[\dfrac{1}{2}-\left(-\dfrac{2}{7}-\dfrac{1}{10}\right)\right]\)
b) \(\dfrac{2}{15}:\left(-5\dfrac{4}{5}\right).2\dfrac{5}{12}+\sqrt{1\dfrac{9}{16}}:\left(-\dfrac{3}{4}\right)\)
bài 1: tính
a) \(\dfrac{5^4.20^4}{25^5.4^5}\) b)3,5-\(\left(-\dfrac{2}{7}\right)\) c)\(\left(\dfrac{11}{12}:\dfrac{33}{16}\right).\dfrac{3}{5}\) d)\(15.\left(-\dfrac{2}{3}\right)^2.-\dfrac{7}{3}\) e)\(\left(\dfrac{9}{25}-2.8\right):\left(3\dfrac{4}{5}+0,2\right)\) g)\(\dfrac{21}{47}+\dfrac{9}{45}+\dfrac{26}{47}+\dfrac{4}{5}\) h)\(\dfrac{15}{12}+\dfrac{5}{13}-\dfrac{3}{12}-\dfrac{18}{13}\) j)12.\(\left(-\dfrac{2}{3}\right)^2+\dfrac{4}{3}\) k)\(\dfrac{13}{25}+\dfrac{6}{41}-\dfrac{38}{25}+\dfrac{35}{41}-\dfrac{1}{2}\) l)12,5.\(\left(-\dfrac{5}{7}\right)+1,5.\left(-\dfrac{5}{7}\right)\) m)\(\sqrt{\dfrac{64}{25}}.3\dfrac{1}{2}-\dfrac{3}{5}.3\dfrac{1}{2}\)
a,\(\dfrac{8^{20}+4^{20}}{4^{25}+64^5}\)
b,\(\left(1+\dfrac{2}{3}-\dfrac{1}{4}\right).\left(\dfrac{4}{5}-\dfrac{3}{4}\right)^2\)
c,\(23\dfrac{1}{3}:\left(\dfrac{-5}{7}\right)-13\dfrac{1}{3}:\left(\dfrac{-5}{7}\right)\)
d,1:\(\left(\dfrac{2}{3}-\dfrac{3}{4}\right)^2\)
e,\(\dfrac{45^{10}.5^{20}}{75^{15}}\)
1 tìm x
a,\(\dfrac{1}{4}x-\left|-\dfrac{3}{10}\right|\)
\(\left(\dfrac{2}{5}-\dfrac{7}{10}x\right):1\dfrac{2}{3}=\dfrac{-3}{4}\)
\(\dfrac{7}{16}:\left(\dfrac{x}{4}+\dfrac{9}{2}\right)-1\dfrac{5}{6}=0\)
1 tìm x
\(\dfrac{3}{4}-\left(2x-\dfrac{2}{3}\right)=\dfrac{-5}{6}\)
\(1,5-\left(x+\dfrac{7}{2}\right)=2^7:2^5\)
\(-12\left(\dfrac{1}{2}-3x\right)^3-\sqrt{16}=\left|-46\right|\)
Tính
a) \(2\sqrt{\dfrac{25}{16}}-3\sqrt{\dfrac{49}{36}}+4\sqrt{\dfrac{81}{64}}\)
b) \(\left(3\sqrt{2}\right)^2-\left(4\sqrt{\dfrac{1}{2}}\right)^2+\dfrac{1}{16}.\left(\sqrt{\dfrac{3}{4}}\right)^2\)
c) \(\dfrac{2}{3}\sqrt{\dfrac{81}{16}}-\dfrac{3}{4}\sqrt{\dfrac{64}{9}}+\dfrac{7}{5}.\sqrt{\dfrac{25}{196}}\)